Bullous pemphigoid associated with a lymphoepithelial cyst of the pancreas.

Bullous pemphigoid (BP) is an acquired, autoimmune, subepidermal blistering disorder. A possible paraneoplastic association has been suggested; however, debate remains regarding the precise relationship of these neoplasms with BP. We present a case of recalcitrant BP in a 67-year-old man with a pancreatic neoplasm that was found to be a lymphoepithelial cyst. Immunoperoxidase staining of the cyst demonstrated C3d along the basement membrane of the stratified squamous epithelium, suggesting that the BP may have involved the lymphoepithelial cyst itself. Shortly after excision of the cyst, BP rapidly resolved without any immunosuppressive treatment, raising the possibility that the immunologic process involving the lymphoepithelial cyst of the pancreas was the inciting factor for the patient's cutaneous disease. Although rare, some cases of BP may be a paraneoplastic process. A thorough screening via patient history and directed laboratory studies may be warranted in recalcitrant cases.